Fuse for bombs



Sept. 15, 1936. H. H. zoRNlG i FUSE FOR BoMBs Filed June 2o, 1935 #IVA l YIIII/l/Illl.

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Inventur Heymann H -Z :wf-Li Attnrna Patented Sept. 15, 1936 PATENT orrlce:

FUSE FOR BOMBS Hermann: H.

Zomg, United States Army,

Newhall, IowaV Application June 20, 1935. .Serial No. 27,531

4 Claims.

(Granted under the act of March 3, 1883, as amended April 30, 1928; 370 O. G. 757) 'Ihe invention described herein may be manufactured and used by or for the Government for governmental purposes, Without the payment to me of any royalty thereon.

This invention relates to a fuse for bombs.

The purpose of the invention is to provide a delay arming mechanism for a. fuse which employs reduced motion gearing.

'I'he invention is characterized by a novel arrangement in which a planet pinion carried by a rotor is meshed with a pair of gears which are both longitudinally displaceable With a spindle.

To these and other ends, the invention consists in the construction, arrangement and combina.- tion of elements described hereinafter and pointed out in the claims forming a part of this specification.

A practical embodiment of the invention is illustrated in the accompanying drawing, where- Fig. 1 is a longitudinal sectional view partly in elevation of a fuse constructed in accordance with the invention and showing the parts in the safe or unarmed position.

Fig. 2 is a similar view with the parts in armed position.

Fig. 3 is a sectional view on the line 3--3 of Fig..1.

Referring to the drawing by characters of reference, there is shown a fuse casing 5 which is attached to a bomb 6 and which carries a ring mechanism comprising a primer 1 and an inertia plunger 8 Whose firing pin 9 is normally held clear of the primer by means of a spring I0. A pin I I in the casing extends into a longitudinally disposed groove I2 in the plunger and holds the plunger against rotation While permitting it to move longitudinally of the casing.

A spindle I3 having its inner end threadedly engaging the plunger 8 and a cap I4 on the vcasing 5, extends through a tube I5 fixed on the cap, and passes through a guide plug I6 in the front end of the tube. 'I'he plug I6 also serves to retain a cup I'I in place on the end of the tube.

The outer projecting end of the spindle carries a sleeve I8 which is secured by means of a pin I3. The sleeve is formed with a ange 28 which cooperates with the inner end of a nut 2I threaded on the sleeve to establish an inner race for ball bearings 22. A rotor 23 has a groove 24 which establishes the outer race for the ball bearings. A ange 25 on the nut 2| extends across the clearance between rotor and nut to protect against entry of foreign matter. A nut 26 on the rotor carries vanes 21 which are acted on by air pressure during night of the bomb to produce rotation of the rotor. The rotor is formed with an apron 28 dimensioned to t Within the cup I'I and enclose elements of the fuse.

A nut 29 on the inner end of the sleeve I8 retains a plate 30 which is movable longitudinally with the spindle but is held against rotational movement by a pin 3| which it carries and which is inserted through an aperture 32 in the oor of the cup I'I.

A gear 33 xed on the plate 30 and having for example twenty-nine teeth is positioned adjacent a gear 34 xed on the sleeve I8 and having for example thirty teeth. A pinion 35 meshing with the gears 33 and 34 is carried on a shaft 3S which is mounted in the rotor 23.

When the fuse is in transportation and storage the plunger 8 and spindle I3 are positively held against movement by their respective cotter pins 31 and 38. These pins are removed when the bomb is placed in the launching rack of an aircraft and an arming wire 39 inserted through apertures in the vane and cup and through a ring 40 secured to the rotor. This arming wire is Withdrawn in a Well known manner when the bomb is launched.

When the bomb is launched the air pressure acts on the vanes to spin the rotor 23 which moves on the ball bearings. 'Ihe pinion 35 carried by the rotor is moved as a planet about the gears 33-34. Since the gear 33 with twentynine teeth is held against rotation the gear 34 with thirty teeth can only move through the distance of one tooth for a complete revolution of the planetary pinion 35. The rotor must therefore revolve twenty-nine times in order to turn the spindle I3 through a single revolution thereby increasing the arming time twenty-nine times, after which the parts are in the position shown in Fig. 2 with the plunger 8 armed and capable of functioning on impact.

I claim:

1. In a fuse, a casing, an element of a ring mechanism in the casing, a cup on one end of the casing, a spindle threaded in said element and passing through the cup, a sleeve xed on the end of the spindle and having a ange, a nut on the sleeve cooperating with the flange to establish an inner race, a rotor having a groove establishing an outer race, ball bearings between the races, vanes on the rotor, a skirt on the rotor dimensioned to lie Within the cup on the casing, a gear xed on the sleeve and disposed Within the skirt of the rotor, a gear non-rotatably carried by the sleeve, said last named gear having less teeth than the xed gear on the sleeve, and a pinion n carried by the rotor and meshing with both of the gears.

2. In a fuse,V a casing, an element of a firing mechanism in the casing, a cup on one end of the Y casing, a spindleV threaded in said element and Y passing through the cup, a sleeve fixed on the end Yof the spindle and having a ange, a nut on the sleeve cooperating with the flange to establish an inner race, a rotor having a groove establishing' an outer race, ball bearings between the races, Y Avanes on theY rotor, a skirt on the rotordimensioned to lie Within the cup onthe casing, and

gearing housed Within the skirt of the rotor'for moving the spindle on rotation ofthe rotor. y

, 3. In a fuse, a casing, anv element of aring mechanism in the casing, a spindle threaded in 2,054,111 Y z Q said element, a sleeve xed on the spindle, a gear xed on the sleeve, a rotor mounted on the sleeve, a plate carried by the sleeve, means for holding the plate against rotation, a gear xed on the plate and having less teeth than the gear on the sleeve, and a pinion carried by the rotor and meshing Withrboth of the gears.

4. In' a fuse, a spindle, a memberV-in'threaded engagement with the spindle, a rotor rotatable relative to the spindle, a gear xed on the spindle, a non-.rotatably mounted gear movable longitudinally With the spindle, said gear having less -teeth than the gear Xed on the spindle, and a pinion carried by the rotor and meshing with both gears.

HERMANN H. ZORNIG. 

